Endoscopic surgical clip applier

ABSTRACT

An apparatus for application of surgical clips to body tissue includes a jaw assembly mounted adjacent a distal end portion of a body, the jaw assembly including first and second jaw portions movable between a spaced-apart and an approximated position; a yoke slidably supported at least partially in a handle portion and being connected to at least one trigger; a drive link slidably supported at least partially in the handle portion and the body, the drive link having a proximal end connected to the yoke; a spindle supported in the body and rotatably connected to the drive link; and a jaw closure member connected to a distal end of the spindle and being positioned adjacent the first and second jaw portions to move the jaw portions to the approximated position upon a squeezing of the at least one trigger which results in distal advancement of the jaw closure member.

CROSS REFERENCE TO RELATED PATENT APPLICATIONS

The instant patent application is a Continuation of U.S. patentapplication Ser. No. 12/764,226, filed on Apr. 21, 2010, which is aDivisional of U.S. patent application Ser. No. 11/245,493, filed on Oct.7, 2005 (now U.S. Pat. No. 7,717,926), which claims priority to each ofU.S. Provisional Patent Application Ser. No. 60/617,104, filed on Oct.8, 2004, and U.S. Provisional Patent Application Ser. No. 60/617,016,filed on Oct. 8, 2004, each of which are herein incorporated byreference in their entirety.

TECHNICAL FIELD

The technical field relates to surgical clip appliers and moreparticularly to an endoscopic surgical clip applier having a mechanismfor stabilizing the jaw structure during the insertion of a surgicalclip.

DESCRIPTION OF THE RELATED ART

Endoscopic staplers and clip appliers are known in the art and are usedfor a number of distinct and useful surgical procedures. In the case ofa laparoscopic surgical procedure, access to the interior of an abdomenis achieved through narrow tubes or cannulas inserted through a smallentrance incision in the skin. Minimally invasive procedures performedelsewhere in the body are often generally referred to as endoscopicprocedures. Typically, a tube or cannula device is extended into thepatient's body through the entrance incision to provide an access port.The port allows the surgeon to insert a number of different surgicalinstruments therethrough using a trocar and for performing surgicalprocedures far removed from the incision.

During a majority of these procedures, the surgeon must often terminatethe flow of blood or another fluid through one or more vessels. Thesurgeon will often apply a surgical clip to a blood vessel or anotherduct to prevent the flow of body fluids therethrough during theprocedure. An endoscopic clip applier is known in the art for applying asingle clip during an entry to the body cavity. Such single clipappliers are typically fabricated from a biocompatible material and areusually compressed over a vessel. Once applied to the vessel, thecompressed clip terminates the flow of fluid therethrough.

One significant design goal is that the surgical clip be loaded betweenthe jaws without any compression of the clip from the loading procedure.Such bending or torque of the clip during loading is disfavored and careis exercised to prevent any damage to the jaws and/or the clip orcompression to the clip by a force during loading. This compressioncould slightly alter the alignment of the clip between the jaws, ordamage the clip causing the surgeon to remove the clip from between thejaws for discarding the clip. Additionally such preloading compressionmay slight compress parts of the clip and change the geometry of theclip. This will cause the surgeon to remove the compressed clip frombetween the jaws for discarding the clip. Accordingly, there is a needfor an apparatus that eliminates one or more of the aforementioneddrawbacks and deficiencies of the art.

SUMMARY

According to a first aspect of the present disclosure, there is providedan apparatus for application of surgical clips to body tissue. Theapparatus has a handle portion with a body extending distally from thehandle portion defining a longitudinal axis and a plurality of surgicalclips disposed within the body. The apparatus also has a jaw assemblymounted adjacent a distal end portion of the body with the jaw assemblyincluding first and second jaw portions movable between a spaced-apartand an approximated position. The apparatus further has a wedge platelongitudinally movable between the first and the second jaw portions,and a clip pusher configured to individually distally advance a surgicalclip to the jaw assembly while the jaw portions are in the spaced apartposition with an actuator. The actuator is at least partially disposedwithin the body and longitudinally movable in response to actuation ofthe handle portion and has a cam link. The apparatus also has a jawclosure member positioned adjacent the first and second jaw portions tomove the jaw portions to the approximated position. The cam linklongitudinally moves wedge plate between the first and the second jawportions.

According to another aspect of the present disclosure, the apparatus hasthe wedge plate biasing the first and the second jaw portions when saidwedge plate is longitudinally moved between the first and the second jawportions and the wedge plate maintains the first and the second jawportions in a fixed predetermined relationship during loading of theclip. The fixed predetermined relationship prevents flexing of the firstand the second jaw members during clip loading.

According to another aspect of the present disclosure, the apparatus hasthe wedge plate with a rounded distal tip.

According to another aspect of the present disclosure, the apparatus hasthe wedge plate with a first proximal window. The first proximal windowis adapted to be engaged by a member disposed in the body with themember being configured to hold the wedge plate in a distal mostposition. The distal most position being between the first and thesecond jaw members.

According to another aspect of the present disclosure, the apparatus hasthe wedge plate with a second proximal window. The second proximalwindow is adapted to be engaged by the member and the second proximalwindow is configured to hold the wedge plate in a proximal most positionretracted from the first and the second jaw members. The proximal mostposition of the wedge plate is configured to allow the first and thesecond jaw members to be moved to the approximated position to compressthe clip.

According to another aspect of the present disclosure, the apparatus hasthe first proximal window connected to the second proximal window by alongitudinal slot.

According to another aspect of the present disclosure, the apparatus hasthe member movable from the second proximal window to first proximalwindow by moving the wedge plate distally.

According to still another aspect of the present disclosure, theapparatus has the cam link engageable with a cam slot in the wedgeplate. The cam slot has a driving edge.

According to another aspect of the present disclosure, the member is aflexible leg.

According to another aspect of the present disclosure, the apparatus hasthe cam slot with a proximal side and a distal side. At the distal side,the cam link traverses past the driving edge at a demarcation line. Atthe demarcation line, the cam link terminates distal movement of thewedge plate.

According to another aspect of the present disclosure, the apparatus hasthe wedge plate further comprising a biasing device. At the demarcationline, the disengagement between the cam link and the driving edgepermits the biasing device to retract the wedge plate.

According to another aspect of the present disclosure, the cam linkdisengages the wedge plate at the demarcation line, and thedisengagement of the cam link permits retraction of the rounded distalend from between the first and the second jaw members.

According to another aspect of the present disclosure, there is providedan apparatus for application of surgical clips to body tissue. Theapparatus has a handle portion and a body extending distally from thehandle portion and defining a longitudinal axis with a plurality ofsurgical clips disposed within the body and a jaw assembly mountedadjacent a distal end portion of the body. The jaw assembly has firstand second jaw portions movable between a spaced-apart and anapproximated position. The apparatus also has a clip pusher configuredto individually distally advance a surgical clip to the jaw assemblywhile the jaw portions are in the spaced apart position and an actuatorat least partially disposed within the body and longitudinally movablein response to actuation of the handle portion. The actuator is biasedto longitudinally move proximally. The apparatus also has a jaw closuremember positioned adjacent the first and second jaw portions to move thejaw portions to the approximated position and a rack having a pluralityof ratchet teeth being connected to the actuator with a pawl biased tothe handle portion. The pawl has at least one tooth configured to engagethe ratchet teeth. As the actuator is moved longitudinally, theplurality of ratchet teeth are passed over the pawl and the pawl isconfigured to prevent inadvertent return of the actuator before fullactuation of the apparatus.

According to another aspect of the present disclosure, the pawl isbiased by a spring and the spring is connected to the handle portion tobias the pawl into engagement with the rack.

According to another aspect of the present disclosure, the apparatus hasthe pawl is pivotally mounted in the handle portion.

According to another aspect of the present disclosure, when actuation ofthe handle portion is terminated in mid stroke, the ratchet teethrestrain the pawl against proximal motion, and any inadvertent partialactuation of the jaw assembly is prevented.

According to another aspect of the present disclosure, the apparatus hasthe first jaw and second portions moved to the approximated position andthe ratchet teeth are advanced a predetermined distance past the pawl topermit retraction of the actuator.

According to another aspect of the present disclosure, there is providedan apparatus for application of surgical clips to body tissue. Theapparatus has a handle assembly with a handle and a trigger movablerelative to the handle, and a body extending distally from the handleportion and defining a longitudinal axis. The apparatus also has aplurality of surgical clips disposed within the body and a jaw assemblymounted adjacent a distal end portion of the body with the jaw assemblyincluding first and second jaw portions movable between a spaced-apartand an approximated position. The apparatus further has a clip pusherconfigured to individually distally advance a surgical clip to the jawassembly while the jaw portions are in the spaced-apart position and anactuator at least partially disposed within the body and longitudinallymovable in response to actuation of the handle portion. The apparatusalso has a link connected at a first end to the actuator and connectedat a second end to the trigger with a jaw closure member positionedadjacent the first and second jaw portions to move the jaw portions tothe approximated position.

According to another aspect of the present disclosure, the link isconnected to a rack having a plurality of ratchet teeth and the ratchetteeth are connected to a pawl and are configured to prevent inadvertentreturn of the actuator before full actuation of the apparatus.

According to another aspect of the present disclosure, the apparatus hasthe pawl biased to the handle. As the trigger is actuated the link isadvanced distally and the link advances the rack distally. The pawlratchet teeth slide along the pawl.

According to another aspect of the present disclosure, the apparatus hasthe pawl is pivotally connected to the handle.

BRIEF DESCRIPTION OF THE DRAWINGS

A particular embodiment of a surgical clip applier is disclosed hereinwith reference to the drawings wherein;

FIG. 1 is a perspective view of a surgical clip applier;

FIG. 2 is another perspective view of the surgical clip applier of FIG.1;

FIG. 3 is an enlarged perspective view of the jaw structure of thesurgical clip applier;

FIG. 4 is a top view of the surgical clip applier;

FIG. 5 is a side view of the surgical clip applier;

FIG. 6 is a side view, with half of the body removed, of the handleassembly of the surgical clip applier;

FIG. 7 is an exploded perspective view of the handle of the clipapplier, with shaft assembly;

FIG. 8 is a perspective view of a pawl;

FIG. 9 is a perspective view of a yoke;

FIG. 10 is an exploded perspective view of the shaft assembly of thesurgical clip applier;

FIG. 10A is a perspective view of a feed bar;

FIG. 10B is a perspective view of a follower and surgical clips;

FIGS. 10C and 10D are opposite perspective views of a trip block;

FIG. 10E is a perspective view of a spindle;

FIG. 10G is an enlarged area of detail of FIG. 10E;

FIG. 10F is an enlarged area of detail of FIG. 10E;

FIG. 11 is a perspective view of the distal end of the spindle and adriver;

FIG. 12 is a perspective view of a trip lever mechanism on the spindle;

FIG. 13 is a perspective view of a wedge plate and biasing spring;

FIGS. 14 and 15 are opposite perspective views of a filler component;

FIG. 16 is a perspective view of the rotation knob and shaft assembly;

FIG. 17 is a perspective view of the overpressure assembly;

FIG. 18 is a perspective view of the spindle and jaw assembly;

FIG. 19 is an enlarged area of detail of the spindle and jaw assembly ofFIG. 18;

FIG. 20 is an enlarged area of detail of the spindle and trip lever ofFIG. 18;

FIG. 21 is an enlarged view of the distal end of the surgical clipapplier with outer tube removed;

FIG. 22 is a perspective view of the surgical clip applier shaftassembly with parts removed;

FIG. 23 is an enlarged area at detail of FIG. 22;

FIG. 24 is an enlarged area of detail of FIG. 22;

FIG. 25 is an enlarged area of detail of FIG. 22;

FIG. 26 is a perspective view of the spindle, driver and jaw assembly;

FIG. 27 is an enlarged area of detail of FIG. 26;

FIG. 27A is a cross-sectional view taken along line 27A-27A of FIG. 27.

FIG. 28 is a perspective view of the cam link and wedge plate assembly;

FIG. 29 is an enlarged area of detail of FIG. 28;

FIG. 30 is an enlarged area of detail of FIG. 29;

FIG. 31 is a perspective view of the filler component and jaw assembly;

FIG. 32 is an enlarged perspective view of the jaw assembly of FIG. 31;

FIGS. 33 and 34 are perspective views of the distal end of the spindleincluding wedge plate and driver;

FIG. 35 is a side view, partially shown in section, of the surgical clipapplier in a pre-fired condition;

FIG. 36 is in enlarged area of detail of FIG. 35;

FIG. 37 is an enlarged area of detail of FIG. 35;

FIG. 38 is in enlarged area of detail of FIG. 37 showing the trip lever;

FIG. 39 is an enlarged area of detail of FIG. 37 showing the follower;

FIG. 40 is an enlarged the area of detail of FIG. 37;

FIG. 41 is enlarged area of detail of FIG. 40;

FIG. 42 is a side view, shown in section, of the distal end of thesurgical clip applier of FIG. 37;

FIG. 43 is a perspective view of the wedge plate and jaw assembly;

FIG. 44 is an enlarged area of detail of FIG. 43 showing the wedge plateand jaw members;

FIG. 45 is a top view of FIG. 43 taken along line 45-45;

FIG. 46 is an enlarged area of detail of FIG. 45 showing the jaw and thewedge plate;

FIG. 47 is an enlarged area of detail of FIG. 45 showing the wedge plateand cam link;

FIG. 48 is a side view, shown in section, of the handle housing at thebeginning of an initial stroke;

FIG. 49 is an enlarged area of detail of FIG. 48 showing the rack andpawl;

FIG. 50 is an enlarged area of detail of FIG. 48 similar to FIG. 49;

FIG. 51 is a side view, shown in section, of the feed bar and triplever;

FIG. 52 is a side view, shown in section, of the follower;

FIG. 53 is a side view, shown in section, of the endoscopic portion ofthe surgical clip applier;

FIG. 54 is an enlarged area of detail of FIG. 53 illustrating thespindle movement;

FIG. 55 is a top view of the wedge plate and filler componentillustrating the movement of the cam link;

FIG. 56 is a side view, shown in section, illustrating the feed baradvancing a clip;

FIG. 57 is a top view of the wedge plate and cam link moving distally;

FIG. 58 is a side view, shown in section, showing the movement of theflexible leg cammed out of a wedge plate window;

FIG. 59 is a side view, shown in section, illustrating a clip enteringthe jaws;

FIG. 60 is a further top view of the cam link and wedge plate movement;

FIG. 61 is a side view, shown in section, of the flexible leg and wedgeplate disengagement;

FIG. 62 is a top view of the wedge plate entering the jaw structure;

FIG. 63 is a perspective view illustrating the wedge plate camming openthe jaw structure;

FIG. 64 is a top view illustrating further advancement of the cam linkin the wedge plate;

FIG. 65 is a side view, shown in section, illustrating the trip leverengaged with the feed bar;

FIG. 66 is a side view, shown in section, illustrating the spindlecamming the flexible leg out of engagement with the wedge plate;

FIG. 67 is a side view, shown in section, illustrating the feed barloading a clip into the jaw structure;

FIG. 68 is a side view, shown in section, illustrating the trip leverbeing cammed out of engagement with the feed bar by means of a tripblock;

FIG. 69 is a side view, shown in section, illustrating the retraction ofthe wedge plate and feed bar;

FIG. 70 is a side view, shown in section, illustrating furtheradvancement of the spindle;

FIG. 71 is a side view, shown in section, illustrating the retraction ofthe wedge plate and further advancement of the spindle;

FIG. 72 is a perspective view of the wedge plate retracting from the jawstructure;

FIG. 73 is a side view, shown in section, with the spindle engaging thedriver and a latch retractor engaging the spindle;

FIG. 74 is a side view of the handle housing with the trigger at fullstroke;

FIG. 75 is an enlarged area of detail of FIG. 74 with the pawl clearingthe ratchet rack;

FIG. 76 is a side view, shown in section, of the driver camming the jawsclosed about a surgical clip;

FIGS. 77 to 79 are sequential views of the driver camming the jawsclosed about a surgical clip;

FIG. 80 is a view, shown in section, of the overpressure mechanismincluding the impact spring;

FIG. 81 is a perspective view of a surgical clip formed on a vessel;

FIG. 82 is an enlarged area of detail of the ratchet mechanismresetting;

FIG. 83 is a side view, shown in section, illustrating the latchretractor resetting;

FIG. 84 is a side view, shown in section, illustrating the spindleretracting; and

FIGS. 85 and 86 are top views illustrating the cam link resetting withinthe wedge plate.

DETAILED DESCRIPTION

There is disclosed a novel endoscopic surgical clip applier having a jawcontrol mechanism configured to maintain jaws of the surgical clipapplier in a spaced apart and stable position during insertion of asurgical clip. It should be noted that, while the disclosed jaw controlmechanism is shown and described in an endoscopic surgical clip applier,the disclosed jaw control mechanism is applicable to any surgical clipapplier or other instrument having a pair of compressible jaws.

Referring now to FIGS. 1-5, surgical clip applier 10 generally includesa handle assembly 12 and an endoscopic portion including an elongatedtubular member 14 extending distally from handle assembly 12. Handleassembly 12 is formed of a plastic material while elongated tubularmember 14 is formed of a biocompatible material such as stainless steel.A pair of jaws 16 are mounted on the distal end of elongated tubularmember 14 and are actuated by a trigger 18 movably mounted in handleassembly 12. Jaws 16 are also formed of a biocompatible material such asstainless steel or titanium. A knob 20 is rotatably mounted on a distalend of handle assembly 12 and affixed to elongated tubular member 14 toprovide 360 degree rotation of elongated tubular member 14 and jaws 16about its longitudinal axis. Referring for the moment to FIG. 3, jaws 16define a channel 22 for receipt of a surgical clip therein.

Referring now to FIGS. 6 and 7, handle assembly 12 of clip applier 10 isshown. Handle assembly 12 includes a longitudinally movable yoke 24connected to trigger 18 by a link 26. Handle assembly 12 includeshousing channels 28 to guide yoke wings 30 of yoke 24 within handleassembly 12 during actuation of clip applier 10. Yoke 24 is connected tothe drive mechanisms and is biased to a proximal position by a returnspring 32. Knob 20 includes a flange 34 which is rotatably mounted in ajournal 36 in housing 12.

Referring to FIGS. 6-9, in order to prevent inadvertent return oftrigger 18 and yoke 24 before full actuation of surgical instrument 10,yoke 24 includes a rack 38 having rack teeth 40. A pawl 42 is pivotallymounted in handle assembly 12 and includes pawl teeth 44 engageable withrack teeth 40. Pawl 42 is biased into engagement with rack 38 by aspring 46. Rack 38 and pawl 42 prevent release of trigger 18 before fullactuation in a manner described in more detail hereinbelow.

Combinations of the various elements and mechanisms associated with clipapplier 10 will now be described.

Referring to FIG. 10, a bushing 48, including retention pins 50, isprovided to secure the bushing 48 to the knob 20. A drive link 52 isconnected, typically with a snap type connection, to yoke 24 such that aproximal end of drive link 52 engages yoke 24. An over pressuremechanism including an impact spring 56 is provided about outer tube 14,between bushing 48 and housed in a bore of knob 20 to prevent overcompression of jaws 16 during actuation of the instrument in a mannerdescribed in more detail hereinbelow. Drive link 52 extends through abore 58 in knob 20.

A flange located at a proximal end of elongated tube member 14 abuts aproximal end of bushing 48.

In order to actuate the various components there is provided anactuation mechanism or spindle 60 mounted for longitudinal movementthrough elongated tubular member 14. Spindle 60 includes a boss 62 atits proximal end which is engageable with a recess 64 on the distal endof drive link 52. A camming mechanism including a driver 66 and a sliderjoint 68 extend from a distal end of spindle 60 to cam closed jaws 16about a surgical clip.

Clip applier 10 is configured to retain a plurality of surgical clipsfor application to tissue. Clip applier 10 includes an elongated channelmember 70 configured to retain a plurality of surgical clips 72 andconvey surgical clips 72 to jaws 16. It should be noted that channelmember 70 and jaws 16 do not move longitudinally relative to elongatedtubular member 14. A follower 74 is biased by a spring 76 to urgesurgical clips 72 distally within channel member 70. A channel cover 78overlies channel 70 to retain and guide spring 76 and surgical clips 72therein. A nose 80 is provided at a distal end of channel cover 78 toassist in directing surgical clips 72 into jaws 16.

A feeder mechanism including a feed bar 82 is provided for longitudinalmovement relative to channel cover 78 in order to advance individualclips 72 into jaws 16. A trip block 84 having a guide pin 86 and a feedbar spring 88 are provided adjacent the proximal end of channel cover 78to bias feed bar 82 in a proximal direction. Specifically, a proximalend 90 of guide pin 86 is interconnected with a hook 92 on an undersideof feed bar 82 (FIGS. 38A & B) and through slot 94 in trip block 84.(See also FIGS. 10 A, C, & D) In order for spindle 60 to move feed bar82, spindle 60 is provided with a trip lever 96 and a biasing spring 98.Trip lever 96 is engageable with a proximal end of feed bar 82 in amanner described in more detail herein below.

A notable advantage of presently disclosed clip applier 10 is that it isprovided with a wedge plate 100 which is configured to advance into jaws16 during actuation of surgical clip applier 10 and maintain jaws 16 ina spaced apart condition while receiving a surgical clip 72. Cam slot136 (FIG. 13), described in detail hereinbelow, formed through wedgeplate 100 and a filler component 102 mounted within elongated tubularmember 14, cooperate in connection with a cam link 104, provided onspindle 60, to move wedge plate 100 relative to filler component 102 andjaws 16. Filler component 102 is positioned directly behind jaws 16 anddoes not move relative to elongated tubular member 14.

Turning to FIG. 10A, and as noted above, feed bar 82 is provided to movesurgical clips 72 into jaws 16. Feed bar 82 is driven by trip lever 96on spindle 60. (See FIG. 10.) Specifically, feed bar 82 is provided withan elongated window 106 which is configured to be engaged by trip lever96 as spindle 60 is driven distally. To facilitate insertion of the clipinto jaws 16, feed bar 82 is provided with a pusher 108 at its distalend which is configured to advance an individual clip 72 out of the lineof clips 72 and into jaws 16. As shown in FIG. 10B, follower 74 ispositioned behind the line of clips to advance clips 72 through surgicalclip applier 10.

Referring to FIG. 10C, as noted above, trip block 84 includes a slot 94to receive hook 92 of feed bar 82. In order to disengage trip lever 96from window 106 and thus feed bar 82, trip block 84 is provided with anangled surfaces 110 which is configured to engage trip lever 96 anddisengage it from window 106 of feed bar 82 as best shown in FIG. 10D.

Referring now to FIGS. 10E-10G, various features of spindle 60 will nowbe described. A perspective view of spindle 60, isolated from othercomponents is shown in FIG. 10E. With specific reference to FIG. 10F, ata proximal end, spindle 60 includes a pivot point 112 for attachment oftrip lever 96 at its proximal end. Additionally, a boss 114 is providedin spindle 60 for attachment of biasing spring 98 to bias trip lever 96into engagement with window 106 of feed bar 82. Similarly, with respectto FIG. 10G, at a distal end, spindle 60 is provided with a boss 116 formounting cam link 104. Spindle 60 is additionally provided with a raisedfeature 118 which functions to disengage filler component 102 from wedgeplate 100 in a manner described in hereinbelow.

Referring to FIG. 11, spindle 60 is provided to advance driver 66 intoengagement with jaws 16 to close jaws 16 about a surgical clip after thesurgical clip has been positioned within jaws 16. A distal end 120 ofslider joint 68 resides in a recess 122 in driver 66. A proximalprojection 124 of slider joint 68 rides within a longitudinal slot 126in the distal end of spindle 60. The length of longitudinal slot 126allows spindle 60 to move a predetermined longitudinal distance beforeengaging and moving driver 66 longitudinally to close jaws 16 about aclip 72. A latch retractor 128 is provided within a slot 130 in sliderjoint 68 so as to allow driver 66 to be driven distally after wedgeplate 100 has been allowed to retract proximally in a manner describedin more detail hereinbelow. A spindle guard 132 is provided betweenlatch retractor 128 and the surface of spindle 60 to prevent damage tothe plastic surface of spindle 60 by the surface of latch retractor 128.

Referring now to FIG. 13, wedge plate 100 will be described in moredetail. As noted above, wedge plate 100 is provided to maintain jaws 16in a spaced apart condition during loading of a surgical clip 72 withinjaws 16. Additionally, the presence of wedge plate 100 providesstability to jaws 16 to prevent them from flexing during loading ofsurgical clip 72. As shown, wedge plate 100 includes a distal tip 134which is configured to engage and cam jaws 16 open and maintain them ina spaced condition. Additionally, wedge plate 100 includes a cam slot136 which is configured to cooperate with cam link 104 mounted onspindle 60 to control the motions of wedge plate 100 as discussed inmore detail below. Further, distal and proximal windows 138 and 140,respectively, are provided to engage flexible structure on the fillercomponent 102. A biasing spring 142 is provided on a mount 144 to biaswedge plate 100 generally proximally within elongated tubular member 14.Finally, a stop 146 is configured to engage corresponding structure onfiller component 102.

Referring now to FIGS. 14 and 15, various aspects of filler component102 will now be described. Filler component 102 includes a flexible leg152 which is configured to engage distal and proximal windows 138 and140 in wedge plate 100. Filler component 102 also includes an elongatedcam slot 148 configured to receive part of cam link 104. A disengagingedge 150 is provided within cam slot 148 to facilitate disengaging camlink 104 from within cam slot 136 in wedge plate 100. Filler component102 additionally includes a recess 154 for engagement with stop 146 onwedge plate 100 (FIG. 13), to limit the proximal retraction of wedgeplate 100, as well as a longitudinal recess 156 to accommodate thelength of return spring 142 of wedge plate 100.

FIGS. 16 and 17 illustrate the position of impact spring 56 relative torotation knob 20. As noted above, impact spring 56 is provided as anover pressure mechanism to prevent over compression of jaws 16 duringthe crimping of a surgical clip 72 as described in more detail belowwith respect to the operation of surgical clip applier 10. The overpressure mechanism is designed to prevent overstroke of trigger 18applied by the surgeon and ultimately prevent damage to jaws 16.

Referring to FIGS. 18-20, spindle 60 and related drive components areshown with elongated tubular member 14 removed. Specifically, withregard to FIG. 19, pusher 108 of feed bar 82 extends through a slot 158in nose 80 to engage a surgical clip 72. Similarly, as shown in FIG. 20,at a proximal end of spindle 60, trip lever 96 extends through window106 in feed bar 82. In this position, trip lever 96 can engage an edgeof slot 106 to drive feed bar 82 distally along with spindle 60 throughelongated tubular member 14.

Referring to FIG. 21, there is a view similar to FIG. 19, however, nose80 has been removed to illustrate pusher 108 engaging a surgical clip 72located in channel 70.

Referring now to FIG. 22, spindle 60 and associated components are shownwith feed bar 82 removed.

Referring to FIG. 23, there are illustrated multiple clips 72 positionedwithin channel 70 for supply to jaws 16 at a distal end of spindle 60.Clips 72 are arranged in longitudinal alignment within channel 70.Retention fingers 71 are provided at a distal end of channel 70 torestrain a stack of clips 72 within channel 70 until advanced into jaws16 by feed bar 82.

Referring to FIG. 24, there is illustrated an intermediate section ofspindle 60 assembled with follower 74 and follower spring 76. As noted,spring 76 biases follower 74 distally relative to spindle 60.

With reference to FIG. 25, there is illustrated spindle 60 assembledwith trip lever 96 and biasing spring 98, with trip lever 96 beingbiased into a upward most position by biasing spring 98.

Referring to FIGS. 26 and 27, an opposed side of spindle 60 assembledwith driver 66 about jaws 16 is illustrated. As noted above, driver 66is configured to cam jaws 16 closed about a surgical clip. Thus, jaws 16include angled camming surfaces 160 for receipt of corresponding cammingsurfaces 184 (FIG. 34) of driver 66. A pocket 187 (FIG. 31) in theproximal end of jaws 16 limits the retraction of driver 66.Specifically, protrusion 186 of slider joint 68 engages pocket 187 ofjaws 16. (See FIGS. 31 & 34).

Referring for the moment to FIG. 27A, camming surfaces 160 on jaws 16and corresponding camming surfaces 184 of driver 66 are smoothlyrounded, curved or radiused. By forming these camming surfaces in thismanner, the friction between camming surfaces 160 and 184 is greatlyreduced providing an improved smooth closure of jaws 16 about clip 72.

Referring to FIGS. 28-30, the relative assembled positions of channel70, trip lock 84, wedge plate 100 and filler component 102 will now bedescribed. Referring initially to FIGS. 29 and 30, filler component 102is positioned on channel 70. Proximal end of filler component 102 abutsa stop 162 positioned on channel 70. The.wedge plate 100 lies overfiller component 102 in the manner shown. As best shown in FIG. 30,filler component 102 includes a cam slot 148 having a disengaging edge150 formed within cam slot 148. Similarly, wedge plate 100 includes acam slot 136. As noted above, a cam link 104 is provided attached tospindle 60 (not shown) in order to drive wedge plate 100 distally. Tofacilitate driving wedge plate 100, cam link 104 is provided with a camlink boss 164 which rides in cam slots 136 and 148 of wedge plate 100and filler component 102 respectively. As cam link 104 is advanceddistally relative to wedge plate 100 cam link boss 164 engages a drivingedge 166 of wedge plate 100 to drive wedge plate 100 distally. In themanner described hereinafter, once cam link 104, and in particular camlink boss 164, engages disengaging edge 150 of filler component 102 camlink boss 164 is cammed out of engagement of driving edge 166.

Referring to FIG. 30, filler component 102 is provided with a flexibleleg 152 which is movable between distal and proximal windows 138, 140,respectively, of wedge plate 100. In order to cam flexible leg 152 outof one of the proximal or distal windows, there is provided a camsurface 168 on flexible leg 152 which cams flexible leg 152 out of thewindows in response to relative movement of wedge plate 100 relative tofiller component 102.

As noted hereinabove, jaws 16 are provided to receive and crimp surgicalclips 72 positioned therein. Referring to FIGS. 31 and 32, jaws 16generally include a pair of flexible legs 170 fixed to a base 172. Jawmembers 16A and 16B are located at a distal end of flexible legs 170. Apair of locking arms 174 extend distally from base 172 and terminate intabs 176. Tabs 176 are configured to engage corresponding holes 177 onelongated tube 14 (FIG. 10) to secure jaws 16 to elongated tube 14. Jaws16 include channel 22 for receipt of surgical clips 72. As shown, fillercomponent 102 is positioned directly behind jaws 16 and, as with jaws16, does not move longitudinally relative to outer tubular member 14.

Referring for the moment to FIG. 32, jaws 16 are configured to receivewedge plate 100 such that the distal tip 134 of wedge plate 100 is usedto initially separate jaws section 16 a and 16 b and maintain them in aseparated and aligned configuration during insertion of a surgical clipinto jaws 16. As noted, this prevents any torquing or flexing of jaw 16a relative to jaw 16 b while a surgical clip 72 is being loaded therein.Each of flexible legs 170 includes a cam edge 178 (see FIGS. 44 & 63) toguide distal tip 134 of wedge plate 100 within jaws 16.

Referring to FIG. 33, wedge plate 100 is illustrated positioned onspindle 60 such that latch retractor 128 extends through a slot 182 inwedge plate 100. As best shown in FIG. 34, with wedge plate 100 removed,it can be seen that a distal end of driver 60 is provided with cammingsurfaces 184. Camming surfaces 184 cooperate with cam surfaces 160 onjaws 16, (see FIG. 27), to cam jaws 16 together in response tolongitudinal movement of driver 60 relative to jaws 16. Protrusion 186on slider joint 68 extends through a slot 188 in wedge plate 100 tolimit retraction of slider joint 68 relative to jaws 16.

The operation of surgical clip applier 10 to crimp a surgical cliparound a target tissue, such as, for example, a vessel, will now bedescribed. With reference to FIGS. 35 and 36, trigger 18 is in agenerally uncompressed state with yoke 24 biased to a proximal-mostposition by return spring 32. As best shown in FIGS. 37-42, and withinitial reference to FIG. 38, in an unfired state, trip lever 96 carriedby spindle 60, biased upwardly by biasing spring 98, is positionedadjacent to, and in contact with, a slot in feed bar 82. Trip block 84is in a distal position relative to trip lever 96.

Referring to FIG. 39, follower 74 is biased distally by a spring 76 suchthat clips 72 are biased in a distal direction.

Referring to FIG. 40, spindle 60 and feed bar 82 are stationery withlatch retractor 128 biased to an upward position.

Referring to FIG. 41, flexible leg 152 of filler component 102 is in thedistal window 138 of wedge plate 100. Raised feature 118 on spindle 60is proximal of flexible leg 152.

As best shown in FIG. 42, at the distal end of surgical clip applier 10,when at rest in an unfired state, wedge plate 100 and feed bar 82 are ina proximal-most position relative to jaws 16.

FIGS. 43-47 illustrate the initial at rest position of the wedge plate100, jaws 16 and filler component 102.

Referring initially to FIGS. 43 and 44, as shown, wedge plate 100 is ina proximal-most position relative to jaws 16. As shown in FIG. 43,flexible leg 152 is in distal window 138 of wedge plate 100, while camlink 104 is in a proximal-most position relative to cam slot 136 inwedge plate 100.

As best shown in FIGS. 45 and 46, wedge plate 100 is in a proximal mostposition relative to jaws 16 with distal tip 134 proximal of cam edges178 of jaws 16.

Referring to FIG. 47, wedge plate 100 is in a proximal-most positionrelative to filler component 102, such that driving edge 166 of wedgeplate 100 is proximal of disengaging edge 150 of filler component 102.

Referring to FIG. 48, to initiate actuation of clip applier 10, trigger18 is moved through an initial swing as shown by arrow A such that link26 drives yoke 24 distally as shown by arrow B. As best shown in FIG.49, as yoke 24 is driven distally in the direction of arrow C, rackteeth 40 on rack 38 slide over pawl teeth 44 on pawl 42. With referencefor the moment to FIG. 50, if the trigger 18 is released at this point,rack teeth 40 would restrain pawl teeth 44 against proximal motion,preventing release of trigger 18 and partial or inadvertent partialactuation of surgical clip applier 10.

During the initial stroke, spindle 60 moves a predetermined distance.With regard to FIG. 51, as spindle 60 is driven an initial distaldistance, trip lever 96 engages elongated window 106 feed bar 82 andmoves feed bar 82 distally a similar distance. As shown in FIGS. 42 &51, as feed bar 82 is driven distally and a clip 72 is driven into jaws16, follower 74 moves distally (FIG. 52) due to the bias of spring 76 tourge the stack of surgical clips 72 distally.

Referring to FIGS. 53 and 54, as spindle 60 and feed bar 82 movedistally, spindle 60 drives cam link 104 distally an initial distancesuch that cam link boss 164 on cam link 104 engages wedge plate 100. Asshown, flexible leg 152 of filler component 102 is positioned indistal-most window 138 of wedge plate 100.

As shown in FIG. 55, as cam link 104 moves distally with spindle 60, camlink boss 164 engages driving edge 166 on wedge plate 100 to urge wedgeplate 100 distally relative to filler component 102.

Referring to FIG. 56, as feed bar 82 moves distally, pusher 108 at thedistal end of feed bar 82 engages a clip 72 and begins to urge clip 72into jaws 16. Notably, at this point, spindle 60 has not yet contacteddriver 66, thereby preventing compression of jaws 16 prior to fullinsertion of surgical clip 72.

Turning again to FIG. 55, as surgical clip applier 10 is actuatedthrough a further second predetermined distance, cam boss 164 on camlink 104 continues to drive wedge plate 100 distally and flexible leg152 is cammed out of distal window 138 and into proximal window 140 bycam surface 168 to engage wedge plate 100 with filler component 102. Asshown in FIGS. 57 & 58, at this point, feed bar 82, wedge plate 100,spindle 60, clips 72 and follower 74 (FIG. 52) are all moving in adistal-most direction.

Referring to FIG. 59, feed bar 82 continues to urge pusher 108 at thedistal end of feed bar 82 against a surgical clip 72 to urge clip 72into channel 22 in jaws 16. Surgical clips 72 contained in channel 70are biased in a distal direction by follower 74 (FIG. 52) and wedgeplate 100 (FIG. 54) continues to move distally while driver 66 remainsstationery relative to elongated tubular member 14.

Referring to FIG. 60, as spindle 60 is moved further, cam boss 164 ofcam link 104 is cammed out of engagement with driving edge 166 of wedgeplate 100 by means of disengaging edge 150 formed in filler component102 as best shown by the arrows in FIG. 60. During this further strokeof a predetermined distance, flexible leg 152 of filler component 102snaps into proximal window 140 of wedge plate 100, thereby preventingretraction of wedge plate 100 from its distal-most position.

As shown in FIG. 61, flexible leg 152 is positioned within proximalwindow 140 of wedge plate 100, thereby restraining wedge plate 100against retraction, while feed bar 82 and spindle 60 continue to move ina distal direction as shown by the arrows.

As shown in FIGS. 62-63, distal tip 134 of wedge plate 100 urges jawmembers 16 a and 16 b apart by engaging cam surfaces 178 in jaw members16 a and 16 b. As noted above, by positioning wedge plate 100 in camsurfaces 178 of jaw members 16 a and 16 b, wedge plate 100 not onlyspreads the jaws 16 apart to properly receive surgical slip 72, butadditionally restrains each individual jaw member 16 a and 16 b fromflexing with respect to each other, thereby preventing any torque ofclip 72 as it is being inserted into jaws 16.

Referring to FIG. 64, as noted above, flexible leg 152 restrains wedgeplate 100 from proximal retraction while cam link 104 continues toadvance through slots 148 and 136 in filler component 102 (FIG. 64) andwedge plate 100.

As best shown in FIG. 65, as spindle 60 continues to move distallythrough the stroke, trip lever 96 is urged distally with spindle 60until trip lever 96 engages camming surface 110 (See FIG. 10D) of tripblock 84. As camming surface 110 of trip block 84 is urged against triplever 96, trip lever 96 will be cammed out of engagement with elongatedwindow 106 of feed bar 82 allowing feed bar 82 to return to a proximalposition due to the bias of feed bar spring 88 (see FIG. 10).

Referring for the moment to FIG. 66, as spindle 60 continues to movethrough its stroke, raised feature 118 on spindle 60 begins to camflexible leg 152 out of proximal window 140 of wedge plate 100, so thatthe wedge plate 100 will be able to retract prior to, and so that,surgical clip 72 is crimped between jaws 16. This is best illustrated inFIG. 67 where feed bar 82 has fully inserted clip 72 within jaws 16 andwedge plate 100 has retracted to a proximal-most position.

FIG. 68 illustrates trip lever 96 being cammed out of engagement withfeed bar 82 by camming surface 110 of trip block 84 and against the biasof biasing spring 98 such that feed bar 82 is disengaged from trip lever96 and feed bar 82 can start to retract proximally. As shown, in FIG.69, pusher 108 of feed bar 82 is retracted to a proximal position behindthe next distal most clip 72 as wedge plate 100 retracts leaving clip 72inserted into jaws 16.

Referring to FIG. 70, trip lever 96 is completely cammed down by camsurface 110 on trip block 84 and spindle 60 continues to move distallythrough a further predetermined stroke.

Referring for the moment to FIG. 71, as wedge plate 100 retractsproximally while spindle 60 continues to move distally, flexible leg 152on filler component 102 snaps into distal window 138 of wedge plate 100.As shown in FIG. 72, wedge plate 100 is retracted to a proximal positionrelative to jaws 16.

Referring to FIG. 73, when latch retractor 128 is cammed downwardlyrelative to spindle 60, spindle 60 has moved distally to a predetermineddistance. The action of spindle 60, now engaging driver 66, pushesdriver 66 distally. Driver 66 draws slider joint 68 and simultaneouslyslider joint 68 drags latch retractor 128 distally mechanically forcingcam surface no. of latch retractor 128 downward to underside of jaw pad172 and engaging latch retractor 128 with slot 126 of spindle 60.

Referring to FIGS. 74-75, as trigger 18 is fully compressed to drivespindle 60 to a distal-most position, rack 38 clears pawl 42 so that theentire drive assembly can retract when the trigger is released. Notably,a full stroke of the spindle 60 is required to take a clip 72 from aninitial position to a fully inserted position in the jaws 16. As spindle60 moves through its distal-most position, it moves driver 66 in themanner described hereinabove to crimp a surgical clip 72. For example,referring to FIGS. 76-79, driver 66 advances distally relative tocamming surfaces 160 on jaws 16 a and 16 b, such that camming surfaces184 on driver 66 cam jaws 16 a and 16 b closed thereby closing surgicalclip 72 contained therebetween.

Referring for the moment to FIG. 80, a security mechanism is provided toprevent an overstroke condition and thereby excessive compression ofclip 72 from damaging tissue, jaws 16 or driver 66. If trigger 18 iscontinued to be squeezed past a stroke required for a full forming ofclip 72 impact spring 56 compresses within the space defined betweenknob 20 and bushing 48 thereby preventing any further distal movement ofspindle 60.

A fully formed clip formed about vessel V is illustrated in FIG. 81.

Referring to FIG. 82, as trigger 18 is released (not shown), pawl 42rotates against the bias of pawl spring 46 such that pawl teeth 44 ridealong rack teeth 40 to reset the handle assembly. As shown in FIG. 83,when driver 66 retracts, latch retractor 128 is again biased up into itsupper-most position, thereby, resetting the drive mechanism.

Referring to FIGS. 84-86, as spindle 60 retracts, raised feature 118 ofspindle 60 moves past flexible leg 152 in filler component 102. Itshould be noted that wedge plate 100 does not move as it has alreadyfully retracted. As spindle 60 retracts, it draws cam link 104proximally within slots 136 and 148 of wedge plate 100 and fillercomponent 102 to its initial position. As best seen in FIG. 86, in thisposition, clip applier 10 is again in an initial position to be refiredand thus to attach another clip to a vessel.

What is claimed is:
 1. An apparatus for application of surgical clips tobody tissue, which comprises: a) a handle portion supporting at leastone trigger; b) a body extending distally from the handle portion anddefining a longitudinal axis; c) a plurality of surgical clips disposedwithin the body; d) a jaw assembly mounted adjacent a distal end portionof the body, the jaw assembly including first and second jaw portionsmovable between a spaced-apart and an approximated position; e) a yokeslidably supported at least partially in the handle portion and beingconnected to the at least one trigger; f) a drive link slidablysupported at least partially in the handle portion and the body, thedrive link having a proximal end connected to the yoke; g) a spindlesupported in the body and rotatably connected to the drive link; and h)a jaw closure member connected to a distal end of the spindle and beingpositioned adjacent the first and second jaw portions to move the jawportions to the approximated position upon a squeezing of the at leastone trigger which results in distal advancement of the jaw closuremember.
 2. The apparatus of claim 1, wherein each of the first andsecond jaw portions includes a camming surface projecting from a surfacethereof, and wherein the jaw closure member includes camming surfacesprojecting from a surface thereof, wherein the camming surfaces of thejaw closure member contact the camming surface of each of the first andsecond jaw portions, upon a squeezing of the at least one trigger, toapproximate the first and second jaw portions.
 3. The apparatus of claim2, wherein the camming surfaces of each of the first and second jawportions has a substantially triangular profile, and the cammingsurfaces of the jaw closure member has a substantially complementaryV-shaped profile.
 4. The apparatus of claim 1, further comprising: arack having a plurality of ratchet teeth being connected to said yoke;and a pawl biased to said handle portion, said pawl having at least onetooth configured to engage said ratchet teeth, wherein as said yoke ismoved longitudinally, said plurality of ratchet teeth are passed oversaid pawl, said pawl configured to prevent inadvertent return of saidyoke before full actuation of the at least one trigger.
 5. The apparatusof claim 4, wherein said pawl is biased by a spring, wherein said springis connected to said handle portion to bias said pawl into engagementwith said rack.
 6. The apparatus of claim 4, wherein said pawl ispivotally mounted in said handle portion.
 7. The apparatus of claim 4,wherein when actuation of said at least one trigger is terminated in midstroke, said plurality of ratchet teeth restrain said pawl againstproximal motion.
 8. The apparatus of claim 4, wherein when said firstjaw and second portions are moved to a fully approximated position, saidplurality of ratchet teeth are advanced completely past said pawl topermit retraction of said yoke.
 9. The apparatus of claim 3, furthercomprising: a rack having a plurality of ratchet teeth being connectedto said yoke; and a pawl biased to said handle portion, said pawl havingat least one tooth configured to engage said ratchet teeth, wherein assaid yoke is moved longitudinally, said plurality of ratchet teeth arepassed over said pawl, said pawl configured to prevent inadvertentreturn of said yoke before full actuation of the at least one trigger.10. The apparatus of claim 3, wherein said pawl is biased by a spring,wherein said spring is connected to said handle portion to bias saidpawl into engagement with said rack.
 11. The apparatus of claim 3,wherein said pawl is pivotally mounted in said handle portion.
 12. Theapparatus of claim 3, wherein when actuation of said at least onetrigger is terminated in mid stroke, said plurality of ratchet teethrestrain said pawl against proximal motion.
 13. The apparatus of claim3, wherein when said first jaw and second portions are moved to a fullyapproximated position, said plurality of ratchet teeth are advancedcompletely past said pawl to permit retraction of said yoke.
 14. Anapparatus for application of surgical clips to body tissue, whichcomprises: a) a handle portion; b) a body extending distally from thehandle portion and defining a longitudinal axis; c) a plurality ofsurgical clips disposed within the body; d) a jaw assembly mountedadjacent a distal end portion of the body, the jaw assembly includingfirst and second jaw portions movable between a spaced-apart and anapproximated position; e) a wedge plate longitudinally movable betweenthe first and the second jaw portions; f) a clip pusher configured toindividually distally advance a surgical clip to the jaw assembly whilethe jaw portions are in the spaced apart position; g) an actuator atleast partially disposed within the body and longitudinally movable inresponse to actuation of the handle portion, the actuator having a camlink; and h) a jaw closure member positioned adjacent the first andsecond jaw portions to move the jaw portions to the approximatedposition, wherein said cam link longitudinally moves said wedge platebetween the first and the second jaw portions.
 15. The apparatus ofclaim 14, wherein said wedge plate biases the first and the second jawportions when said wedge plate is longitudinally moved between the firstand the second jaw portions; and wherein said wedge plate maintains saidfirst and said second jaw portions in a fixed predetermined relationshipduring loading of said clip, said fixed predetermined relationshippreventing flexing of the first and the second jaw members during cliploading.
 16. The apparatus of claim 14, wherein said wedge plate has arounded distal tip.
 17. The apparatus of claim 15, wherein said wedgeplate has a first proximal window, said first proximal window adapted tobe engaged by a member disposed in said body, said member beingconfigured to hold said wedge plate in a distal most position, saiddistal most position being between said first and said second jawmembers.
 18. The apparatus of claim 17, wherein said wedge plate has asecond proximal window, said second proximal window adapted to beengaged by said member, said second proximal window configured to holdsaid wedge plate in a proximal most position being retracted from saidfirst and said second jaw members, said proximal most position of saidwedge plate configured to allow the first and the second jaw members tobe moved to the approximated position to compress said clip.
 19. Theapparatus of claim 18, wherein said first proximal window is connectedto said second proximal window by a longitudinal slot.
 20. The apparatusof claim 18, wherein said member is movable from said second proximalwindow to first proximal window by moving said wedge plate distally. 21.The apparatus of claim 14, wherein said cam link is engageable with acam slot in said wedge plate, wherein said cam slot is has a drivingedge.
 22. The apparatus of claim 17, wherein said member is a flexibleleg.
 23. The apparatus of claim 21, wherein said cam slot has a proximalside and a distal side, wherein at said distal side said cam linktraverses past said driving edge at a demarcation line, and wherein atsaid demarcation line said cam link terminates distal movement of saidwedge plate.
 24. The apparatus of claim 23, wherein said wedge platefurther comprises a biasing device, and wherein at said demarcation linethe disengagement between said cam link and said driving edge permitssaid biasing device to retract said wedge plate.
 25. The apparatus ofclaim 24, wherein said cam link disengages said wedge plate at saiddemarcation line, and wherein the disengagement of said cam link permitsretraction of said rounded distal end from between said first and saidsecond jaw members.
 26. An apparatus for application of surgical clipsto body tissue, which comprises: a) a handle portion; b) a bodyextending distally from the handle portion and defining a longitudinalaxis; c) a plurality of surgical clips disposed within the body; d) ajaw assembly mounted adjacent a distal end portion of the body, the jawassembly including first and second jaw portions movable between aspaced-apart and an approximated position; e) a clip pusher configuredto individually distally advance a surgical clip to the jaw assemblywhile the jaw portions are in the spaced apart position; f) an actuatorat least partially disposed within the body and longitudinally movablein response to actuation of the handle portion, said actuator beingbiased to longitudinally move proximally; g) a jaw closure memberpositioned adjacent the first and second jaw portions to move the jawportions to the approximated position; h) a rack having a plurality ofratchet teeth being connected to said actuator; and i) a pawl biased tosaid handle portion, said pawl having at least one tooth configured toengage said ratchet teeth, wherein as said actuator is movedlongitudinally, said plurality of ratchet teeth are passed over saidpawl, said pawl configured to prevent inadvertent return of saidactuator before full actuation of the apparatus.
 27. The apparatus ofclaim 26, wherein said pawl is biased by a spring, wherein said springis connected to said handle portion to bias said pawl into engagementwith said rack.
 28. The apparatus of claim 26, wherein said pawl ispivotally mounted in said handle portion.
 29. The apparatus of claim 26,wherein when actuation of said handle portion is terminated in midstroke, said plurality of ratchet teeth restrain said pawl againstproximal motion, and wherein any inadvertent partial actuation of saidjaw assembly is prevented.
 30. The apparatus of claim 26, wherein whensaid first jaw and second portions are moved to the approximatedposition, said plurality of ratchet teeth are advanced a predetermineddistance past said pawl to permit retraction of said actuator.